U.S. patent application number 14/762978 was filed with the patent office on 2015-12-17 for unique identification of coin or other object.
This patent application is currently assigned to ARJOWIGGINS SOLUTIONS. The applicant listed for this patent is ARJOWIGGINS SOLUTIONS, MONNAIE ROYALE CANADIENNE/ROYAL CANADIAN MINT, SIGNOPTIC TECHNOLOGIES. Invention is credited to Yann BOUTANT, Hieu TRUONG.
Application Number | 20150363990 14/762978 |
Document ID | / |
Family ID | 51226772 |
Filed Date | 2015-12-17 |
United States Patent
Application |
20150363990 |
Kind Code |
A1 |
TRUONG; Hieu ; et
al. |
December 17, 2015 |
UNIQUE IDENTIFICATION OF COIN OR OTHER OBJECT
Abstract
A method of producing an authenticatable article. An overt
feature is produced in the article using a fabricating technique
which is selected based on a material of the article so as to
produce the overt feature having predetermined, reproducible
macroscopic characteristics as well as random, non-reproducible
microscopic characteristics rendering the article physically
unique. The overt feature including the microscopic characteristics
are imageable using a predetermined imaging technology to produce
an overt feature image. An authentication signature is generated
based on the overt feature image and stored in a central database.
The overt feature may alternatively be produced in an apparatus or
means used to manufacture authenticatable articles such that the
overt feature including the random, microscopic characteristics is
reproduced in the articles. The overt feature and generated
authentication code therefore corresponds to articles manufactured
using that apparatus or means.
Inventors: |
TRUONG; Hieu; (Orleans,
CA) ; BOUTANT; Yann; (Chindrieux, FR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SIGNOPTIC TECHNOLOGIES
ARJOWIGGINS SOLUTIONS
MONNAIE ROYALE CANADIENNE/ROYAL CANADIAN MINT |
Le Bourget du Lac
Boulogne Billancourt
Ottawa |
|
FR
FR
CA |
|
|
Assignee: |
ARJOWIGGINS SOLUTIONS
Boulogne, Billancourt
ON
MONNAIE ROYALE CANADIENNE/ROYAL CANADIAN MINT
Ottawa
|
Family ID: |
51226772 |
Appl. No.: |
14/762978 |
Filed: |
April 30, 2013 |
PCT Filed: |
April 30, 2013 |
PCT NO: |
PCT/CA2013/050333 |
371 Date: |
July 23, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61756301 |
Jan 24, 2013 |
|
|
|
Current U.S.
Class: |
382/136 |
Current CPC
Class: |
B42D 2035/34 20130101;
G07D 7/20 20130101; A44C 21/00 20130101; G07D 7/003 20170501; G06K
9/4604 20130101; G07D 5/005 20130101 |
International
Class: |
G07D 5/00 20060101
G07D005/00; G07D 7/00 20060101 G07D007/00; G07D 7/20 20060101
G07D007/20; G06K 9/46 20060101 G06K009/46 |
Claims
1. A method of producing an authenticatable article, the method
comprising: producing in the article an overt feature using a
fabricating technique, the fabricating technique being selected
based on a material of the article so as to produce the overt
feature having predetermined, reproducible macroscopic
characteristics as well as random, non-reproducible microscopic
characteristics, wherein the microscopic characteristics are
imageable using a predetermined imaging technology; imaging the
overt feature using the predetermined imaging technology to produce
an overt feature image; generating an authentication signature
based on the overt feature image; and storing the authentication
signature in a central database.
2. The method according to claim 1, wherein the predetermined,
reproducible macroscopic characteristics of the overt feature
comprise a size or a shape of the overt feature.
3. The method according to claim 2, wherein the shape of the overt
feature comprises a code, a symbol, a graphic, or an alpha-numeric
character, and wherein the size of the overt feature renders the
shape discernible to a naked eye.
4. The method according to claim 2, wherein the shape of the overt
feature comprises a code, a symbol, a graphic, or an alpha-numeric
character, and wherein the size of the overt feature renders the
shape discernible only under magnification.
5. The method according to claim 4, wherein the shape comprises an
identification code associated with production or logistic data for
performing tracking, tracing, or quality control of the
article.
6. The method according to claim 5, wherein the identification code
comprises an access key to a database storing the production or
logistic data, or a public key for use with a cryptographic
algorithm.
7. The method according to claim 1, wherein the random,
non-reproducible microscopic characteristics of the overt feature
comprise a predetermined resolution, coarseness, surface roughness,
or other property enabling reproducible imaging of the random,
non-reproducible microscopic characteristics using the
predetermined imaging technology.
8. The method according to claim 7, wherein the non-reproducible
microscopic characteristics are reproducibly imageable using the
predetermined imaging technology under about 20.times.
magnification.
9. The method according to claim 1 further comprising measuring or
imaging a covert feature of the article, the covert feature
comprising a different aspect of the article non-deducible from an
inspection of the article, and wherein the authentication signature
is further generated based on a measurement or image of the covert
feature.
10. The method according to claim 1, wherein the article is a coin,
wherein the material of the coin is a metal or metal alloy, and
wherein the fabricating technique comprises laser engraving, acid
etching, photosensitive etching, random dot machine engraving, or
sandblasting.
11. The method according to claim 10, wherein the article is a
bullion coin, wherein the material of the article is gold or
platinum, and wherein the fabricating technique comprises laser
engraving.
12. The method according to claim 1, wherein the fabricating
technique is incapable of exactly reproducing the non-reproducible
microscopic characteristics, whereby the non-reproducible
microscopic characteristics render the article physically
unique.
13. A method of authenticating an authenticatable article
comprising an overt feature having predetermined, reproducible
macroscopic characteristics as well as random, non-reproducible
microscopic characteristics, the random, non-reproducible
microscopic characteristics rendering the article physically
unique, the method comprising: imaging the overt feature using a
predetermined imaging technology to produce an overt feature image;
generating an authentication signature based on the overt feature
image; sending the authentication signature to a predetermined
central server; and receiving from the predetermined central server
an indication that the authentication signature matches a stored
authentication signature within predefined tolerances.
14. The method according to claim 13, wherein the overt feature is
imaged at a location remote to the central server.
15. A method of producing authenticatable articles, the method
comprising: producing in an apparatus or means used to manufacture
the articles an overt feature using a fabricating technique, the
fabricating technique being selected based on a material of the
apparatus or means so as to produce the overt feature having
predetermined, reproducible macroscopic characteristics as well as
random, non-reproducible microscopic characteristics; reproducing
the overt feature in the articles when the articles are
manufactured using the apparatus or means, wherein the microscopic
characteristics are imageable from the articles using a
predetermined imaging technology; imaging the overt feature using
the predetermined imaging technology from at least one of the
articles to produce an overt feature image; generating an
authentication signature based on the overt feature image; and
storing the authentication signature in a central database.
16. The method according to claim 15, wherein the articles are
coins, and wherein the apparatus or means comprises a die, a punch,
or a matrix.
17. The method according to claim 16, wherein the material of the
die, the punch, or the matrix is a metal or metal alloy, and
wherein the fabricating technique comprises laser engraving, acid
etching, photosensitive etching, random dot machine engraving, or
sandblasting.
18. The method according to claim 15, wherein the predetermined,
reproducible macroscopic characteristics of the overt feature
comprise a size or a shape of the overt feature.
19. The method according to claim 18, wherein the shape of the
overt feature comprises a code, a symbol, a graphic, or an
alpha-numeric character, and wherein the size of the overt feature
is such that the shape is discernible to a naked eye.
20. The method according to claim 18, wherein the shape of the
overt feature comprises a code, a symbol, a graphic, or an
alpha-numeric character, and wherein the size of the overt feature
is such that the shape is discernible under magnification.
21. The method according to claim 20, wherein the shape comprises
an identification code associated with production or logistic data
for performing tracking, tracing, or quality control of the
articles.
22. The method according to claim 21, wherein the identification
code comprises an access key to a database storing the production
or logistic data, or a public key for use with a cryptographic
algorithm.
23. The method according to claim 18, wherein the random,
non-reproducible microscopic characteristics of the overt feature
comprise a predetermined resolution, coarseness, surface roughness,
or other property enabling reproducible imaging of the random,
non-reproducible microscopic characteristics using the
predetermined imaging technology.
24. The method according to claim 23, wherein the non-reproducible
microscopic characteristics are reproducibly imageable using the
predetermined imaging technology under about 20.times.
magnification.
25. The method according to claim 18 further comprising measuring
or imaging a covert feature of the at least one article, the covert
feature comprising a different aspect of the article non-deducible
from an inspection of the article, and wherein the authentication
signature is further generated based on a measurement or image of
the covert feature.
26. The method according to claim 18, wherein the fabricating
technique is incapable of exactly reproducing the non-reproducible
microscopic characteristics, whereby the non-reproducible
microscopic characteristics render the apparatus or means
physically unique.
27. The method according to claim 18, wherein the at least one
article is a first one of the articles manufactured using the
apparatus or means at a first time during a production process,
wherein a second one of the articles is manufactured using the
apparatus or means at a second time during the production process,
the second time being different from the first time, wherein the
overt feature is characterized by a first condition of wear at the
first time, and wherein the overt feature is characterized by a
second condition of wear at the second time, the second condition
of wear being different from the first condition of wear, wherein
the microscopic characteristics imageable from the first article
are characterized by the first condition of wear, wherein the
microscopic characteristics imageable from the second article are
characterized by the second condition of wear, wherein the overt
feature image produced by imaging the overt feature from the first
article is a first overt feature image characterized by the first
condition of wear, and wherein the authentication signature is a
first authentication signature characterized by the first condition
of wear, the method further comprising: imaging the overt feature
using the predetermined imaging technology from the second article
to produce a second overt feature image characterized by the second
condition of wear; generating a second authentication signature
based on the second overt feature image and characterized by the
second condition of wear; and storing the second authentication
signature in the central database.
28. The method according to claim 27, further comprising storing
the first authentication signature in the central database in
association with the first time, and storing the second
authentication signature in the central database in association
with the second time.
29. The method according to claim 27 further comprising determining
based on the second overt feature image that the second condition
of wear exceeds an predefined acceptable level of wear.
30. A method of authenticating articles, the method comprising:
producing in an apparatus or means used to manufacture the articles
an overt feature using a fabricating technique, the fabricating
technique being selected based on a material of the apparatus or
means so as to produce the overt feature having predetermined,
reproducible macroscopic characteristics as well as random,
non-reproducible microscopic characteristics; reproducing the overt
feature in the articles when the articles are manufactured using
the apparatus or means, wherein the microscopic characteristics are
imageable from the articles using a predetermined imaging
technology; using the predetermined imaging technology, imaging the
overt feature from selected ones of the articles manufactured at
predetermined different times during a production process of the
articles to produce corresponding overt feature images; generating
at least one authentication signature based on the overt feature
images; and storing the least one authentication signature in a
central database.
31. The method according to claim 30, wherein a different
authentication signature is generated based on each one of the
overt feature images, and wherein each of the different
authentication signatures is stored in the central database in
association with the corresponding predetermined different
time.
32. The method according to claim 31, wherein the at least one
authentication signature comprises a single authentication
signature recalculated at each predetermined different time based
on an original authentication signature generated at a first one of
the predetermined different times and further authentication
signatures generated at further ones of the predetermined different
times.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to object
authentication and more particularly to object authentication based
on physical characteristics.
BACKGROUND OF THE INVENTION
[0002] It is well known that articles of trade and commerce whose
value depends upon authenticity are subject to counterfeit. Such
articles include currency such as coins and banknotes, and
investment commodities such as bullion coins and bars, but may also
include luxury items such as designer apparel and accessories. In
some cases, such as banknotes, substantially all of the value of
the article may derive from its authenticity, that is the
confidence that it is what it appears to be which may concern its
materials, utility, or its source or conditions of manufacture.
[0003] Many methods and techniques have been developed to enable
authentication of valuable articles and are generally directed to
enabling a person to distinguish between authentic articles and
counterfeit articles. In some cases, authentication undesirably
requires alteration to the article being authenticated. For
example, gold coins and gold wafers are an investment means which
people buy either to invest or to save. Gold can be determined as
real gold through traditional methods such as chemical assays,
instrumental analysis assays, fire assays, stone assays, and so
forth. All of these methods are destructive, however, and require
equipment, expertise, know-how, experience, and time. In addition,
the authentication services may not be easily accessible to the
public where and when needed.
[0004] Alternatively, some methods do not require alteration of the
article, but instead rely upon preexisting physicochemical
characteristics of the article which may be measured and used to
generate an identifier associated with the article and which is
subsequently used in its remote authentication. For example, World
Intellectual Property Organization International Publication Number
WO 2012/145842 by the present inventors, and which is incorporated
herein in its entirety, discloses a method wherein an image of an
article, specifically a coin, is captured and a digital
representation of an acquisition area of the coin including a
feature is generated. The feature may include a first component
common to more than one coin and a second component unique to the
coin. The feature may be random, such as naturally occurring
features resulting from handling or processing during manufacture,
or may be deterministic such as an intentionally applied feature
produced by known fabrication techniques. An identifier is
generated based on the digital representation of the feature and is
later used to authenticate the coin.
[0005] The above method suffers the disadvantage, however, that for
certain materials such as dense metals like gold, the random,
naturally occurring features are relatively fine-grained and not
distinguishable at low magnification, e.g. about 20 times.
Producing digital representations of such naturally occurring
features in such a case which are sufficiently reliable for the
purposes of authentication thus requires relatively expensive
equipment which is not typically available to a wide variety of
users. Accordingly, the method may not permit convenient
implementation for such materials using inexpensive, ubiquitous
equipment available to a wide variety of users.
[0006] While the above solutions enable a high level of security
including authentication, further improvements are possible and
desirable. In particular, it is desirable to provide a method which
renders as difficult as possible any forgery or false
authentication by a counterfeiter, but at the same time enables
quick and reliable authentication without need for special
expertise or equipment.
SUMMARY OF THE INVENTION
[0007] The above advantages may be provided by systems and methods
wherein a valuable article is physically transformed using a
technology which results intentionally in an overt, visible feature
with at least some macroscopic characteristics which are
predetermined, such as its shape and size, but also with at least
some characteristics which are random or probabilistic in nature
thereby rendering the feature non-reproducible by the technology
employed. This overt feature may be produced using any convenient
fabricating technique according to the article material involved.
The fabricating technique may be selected based on the material so
as to generate the random or probabilistic characteristics having a
predetermined resolution, coarseness, surface roughness, or such
other property as enables reliable imaging using simple,
inexpensive, and commonly available imaging technology. For
example, and without limiting the generality of the invention, the
fabricating technique may be selected such that the random or
probabilistic characteristics are capable of reliable digital
imaging at a magnification of about 20 times. For example, where
the article is a coin, useful fabricating techniques include laser
engraving, acid etching, photosensitive etching, random dot machine
engraving, sandblasting, and so forth. Such techniques are useful
to transform a natural topography of the article material into an
irreversible, permanent, and impossible to replicate physical
feature having a visibly changed appearance of the material, while
at the macroscopic level rendering a reproducible physical
form.
[0008] This material transformation resulting from the fabrication
of the feature may be considered to be an overt security feature
and enables authentication of the article by virtue of the fact
that it cannot be exactly reproduced thereby rendering the article
physically unique. In addition, other aspects of the article may be
used along with the measured random feature in order to generate an
authentication signature useful to authenticate the article. The
selection of such other aspects may not be apparent from the
article itself and may thus be considered a covert security feature
as it will not generally be possible for a prospective
counterfeiter to deduce how to forge the authentication signature
based only on an analysis of an authentic article.
[0009] The valuable article according to the invention physically
transformed comprises, by means of the overt visible feature, a
"first level" security feature which can allow authenticating of
the article with naked eye. For instance, the "first level"
security feature may comprise a code, a symbol, a graphic or
alpha-numeric character. However, it can also comprise "second
level" and/or "third level" security feature.
[0010] Advantageously, the valuable article according to the
present invention may comprise a "second level" security feature,
preferably integrated in, part of or combined with the overt
visible feature. For instance, this "second level" security feature
may comprise a code, a symbol, a graphic or alpha-numeric
character, such as year of production, visible by means of a simple
device such as a magnifying glass.
[0011] In another aspect of the invention, the "second level"
security feature is an identification code which can be associated
with production and/or logistic data in order to carry out the
tracking and tracing and/or quality control of individual or family
valuable article. Alternatively, this identification code can be
either an access key to a database in which production and/or
logistic data are recorded, or a public key for cryptography
algorithm such as "Rivest Shamir Adleman" algorithm (RSA) or any
other asymmetric encryption algorithm.
[0012] Additionally, the valuable article according to the
invention physically transformed comprises, by means of the
non-reproducible random feature intentionally produced, a "third
level" security feature which can allow the generation of an
authentication signature.
[0013] Thus, an authentication signature may be generated based on
a measurement or digitized image of the non-reproducible random
feature intentionally produced in the article as well as other
aspects of the article whose selection is not determinable from the
article itself. The authentication signature may then be stored in
a central database. Later authentication of the article then
proceeds by again measuring or imaging the random feature and
reproducing the method of generating the authentication signature,
which may be performed at least in part at a location remote to the
article such as a central server. If the original and later
authentication signatures agree within predefined tolerances then
the article is identified as authentic, and if not it is identified
as inauthentic or suspect.
[0014] Alternatively, the random feature may be applied to whatever
apparatus or other means is used to fabricate the article in the
first place which then results in a reproduction of the feature or
a version thereof on the article itself. For example, where the
article is a coin, the random feature may be applied to the die,
punch, or matrix used to make the coin, in which case all coins
produced using that die, punch, or matrix will bear the feature. In
such case, measuring and recording the feature and generation of a
signature therefrom serves to identify and authenticate all of the
articles produced using that means, such as all of the coins
produced using a particular die, etc.
[0015] In case random feature is applied to the die, punch, or
matrix to make the coin, an additional step of sampling several
reference authentication signatures generated from random feature
during production process allow subsequent control and/or
adaptation of the signature generation thereby improving
authenticating process. Indeed, due the wear of the die the
authentication signature may vary during production time.
Therefore, for example, authentication signatures in the beginning,
middle, end of the production process can be set as reference
signatures in order to take into account the wear effect of the die
in the authentication signatures generation, thereby improving it.
Such reference signatures are used to define the time position of a
particular coin in the production process, beginning, middle or end
of the process. Time position is preferably recorded in database in
correspondence with corresponding authentication signature. This
information can there be retrieved during authenticating subsequent
step. Moreover, a control of the reference signature, or a
comparison between subsequent reference signatures, allow to detect
a unexpected trouble in the production process or a die which wear
is no more acceptable therefore the next correcting step is for
instance the cleaning of the die or its replacement.
[0016] In either case, the article may be traced to the original
location of manufacturing and thus authentication may be performed
via any means capable of generating the requisite measurement or
image of the feature anywhere in the world.
[0017] Thus, in a first embodiment, a method of producing an
authenticatable article has the following steps. An overt feature
is produced in the article using a fabricating technique, the
fabricating technique being selected based on a material of the
article so as to produce the overt feature having predetermined,
reproducible macroscopic characteristics as well as random,
non-reproducible microscopic characteristics, wherein the
microscopic characteristics are imageable using a predetermined
imaging technology. The overt feature is imaged using the
predetermined imaging technology to produce an overt feature image.
An authentication signature is generated based on the overt feature
image. The authentication signature is stored in a central
database.
[0018] The predetermined, reproducible macroscopic characteristics
of the overt feature may comprise a size or a shape of the overt
feature. The shape of the overt feature may comprise a code, a
symbol, a graphic, or an alpha-numeric character, wherein the size
of the overt feature renders the shape discernible to a naked eye,
or wherein the size of the overt feature renders the shape
discernible only under magnification. The shape may comprise an
identification code associated with production or logistic data for
performing tracking, tracing, or quality control of the article.
The identification code may comprise an access key to a database
storing the production or logistic data, or a public key for use
with a cryptographic algorithm.
[0019] The random, non-reproducible microscopic characteristics of
the overt feature may comprise a predetermined resolution,
coarseness, surface roughness, or other property enabling
reproducible imaging of the random, non-reproducible microscopic
characteristics using the predetermined imaging technology. The
non-reproducible microscopic characteristics may be reproducibly
imageable using the predetermined imaging technology under about
20.times. magnification.
[0020] The method may further include measuring or imaging a covert
feature of the article, the covert feature comprising a different
aspect of the article non-deducible from an inspection of the
article, wherein the authentication signature is further generated
based on a measurement or image of the covert feature.
[0021] The article may be a coin, wherein the material of the coin
is a metal or metal alloy, and wherein the fabricating technique
comprises laser engraving, acid etching, photosensitive etching,
random dot machine engraving, or sandblasting. The article may be a
bullion coin, wherein the material of the article is gold or
platinum, and wherein the fabricating technique comprises laser
engraving.
[0022] The fabricating technique may be incapable of exactly
reproducing the non-reproducible microscopic characteristics,
whereby the non-reproducible microscopic characteristics render the
article physically unique.
[0023] In a second embodiment, a method of authenticating an
authenticatable article comprises the following steps. An overt
feature has predetermined, reproducible macroscopic characteristics
as well as random, non-reproducible microscopic characteristics,
the random, non-reproducible microscopic characteristics rendering
the article physically unique. The overt feature is imaged using a
predetermined imaging technology to produce an overt feature image.
An authentication signature is generated based on the overt feature
image. The authentication signature is sent to a predetermined
central server. An indication is received from the predetermined
central server that the authentication signature matches a stored
authentication signature within predefined tolerances. The overt
feature may be imaged at a location remote to the central
server.
[0024] In a third embodiment, a method of producing authenticatable
articles has the following steps. An overt feature is produced in
an apparatus or means used to manufacture the articles using a
fabricating technique selected based on a material of the apparatus
or means so as to produce the overt feature having predetermined,
reproducible macroscopic characteristics as well as random,
non-reproducible microscopic characteristics. The overt feature is
reproduced in the articles when the articles are manufactured using
the apparatus or means, wherein the microscopic characteristics are
imageable from the articles using a predetermined imaging
technology. The overt feature is imaged using the predetermined
imaging technology from at least one of the articles to produce an
overt feature image. An authentication signature is generated based
on the overt feature image. The authentication signature is stored
in a central database.
[0025] The articles may be coins, wherein the apparatus or means
comprises a die, a punch, or a matrix. The material of the die, the
punch, or the matrix may be a metal or metal alloy, wherein the
fabricating technique may comprise laser engraving, acid etching,
photosensitive etching, random dot machine engraving, or
sandblasting.
[0026] The predetermined, reproducible macroscopic characteristics
of the overt feature may comprise a size or a shape of the overt
feature. The shape of the overt feature may comprise a code, a
symbol, a graphic, or an alpha-numeric character, wherein the size
of the overt feature is such that the shape is discernible to a
naked eye, or wherein the size of the overt feature is such that
the shape is discernible under magnification. The shape may
comprise an identification code associated with production or
logistic data for performing tracking, tracing, or quality control
of the articles. The identification code may comprise an access key
to a database storing the production or logistic data, or a public
key for use with a cryptographic algorithm.
[0027] The random, non-reproducible microscopic characteristics of
the overt feature may comprise a predetermined resolution,
coarseness, surface roughness, or other property enabling
reproducible imaging of the random, non-reproducible microscopic
characteristics using the predetermined imaging technology. The
non-reproducible microscopic characteristics may be reproducibly
imageable using the predetermined imaging technology under about
20.times. magnification.
[0028] The method may further comprise measuring or imaging a
covert feature of the at least one article, the covert feature
comprising a different aspect of the article non-deducible from an
inspection of the article, and wherein the authentication signature
is further generated based on a measurement or image of the covert
feature.
[0029] The fabricating technique may be incapable of exactly
reproducing the non-reproducible microscopic characteristics,
whereby the non-reproducible microscopic characteristics render the
apparatus or means physically unique.
[0030] In a further embodiment based on the third embodiment, the
at least one article is a first one of the articles manufactured
using the apparatus or means at a first time during a production
process, and a second one of the articles is manufactured using the
apparatus or means at a second time during the production process,
the second time being different from the first time. The overt
feature is characterized by a first condition of wear at the first
time, and the overt feature is characterized by a second condition
of wear at the second time, the second condition of wear being
different from the first condition of wear. The microscopic
characteristics imageable from the first article are characterized
by the first condition of wear, and the microscopic characteristics
imageable from the second article are characterized by the second
condition of wear. The overt feature image produced by imaging the
overt feature from the first article is a first overt feature image
characterized by the first condition of wear, and the
authentication signature is a first authentication signature
characterized by the first condition of wear. The method further
comprises the following steps. The overt feature is imaged using
the predetermined imaging technology from the second article to
produce a second overt feature image characterized by the second
condition of wear. A second authentication signature is generated
based on the second overt feature image and characterized by the
second condition of wear. The second authentication signature is
stored in the central database.
[0031] The method may further comprise storing the first
authentication signature in the central database in association
with the first time, and storing the second authentication
signature in the central database in association with the second
time.
[0032] The method may further comprise determining based on the
second overt feature image that the second condition of wear
exceeds an predefined acceptable level of wear.
[0033] In a fourth embodiment, a method of authenticating articles
includes the following steps. An overt feature is produced using a
fabricating technique in an apparatus or means used to manufacture
the articles. The fabricating technique is selected based on a
material of the apparatus or means so as to produce the overt
feature having predetermined, reproducible macroscopic
characteristics as well as random, non-reproducible microscopic
characteristics. The overt feature is reproduced in the articles
when the articles are manufactured using the apparatus or means,
wherein the microscopic characteristics are imageable from the
articles using a predetermined imaging technology. Using the
predetermined imaging technology, the overt feature is imaged from
selected ones of the articles manufactured at predetermined
different times during a production process of the articles to
produce corresponding overt feature images. At least one
authentication signature is generated based on the overt feature
images. The least one authentication signature is stored in a
central database.
[0034] A different authentication signature may be generated based
on each one of the overt feature images, wherein each of the
different authentication signatures is stored in the central
database in association with the corresponding predetermined
different time.
[0035] The at least one authentication signature may comprise a
single authentication signature recalculated as a moving average at
each predetermined different time based on an original
authentication signature generated at a first one of the
predetermined different times and further authentication signatures
generated at further ones of the predetermined different times.
[0036] Other aspects and features of the present invention will
become apparent to those ordinarily skilled in the art upon review
of the following description of specific embodiments of the
invention in conjunction with the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] Embodiments of the present invention will now be described,
by way of example only, with reference to the attached Figures,
wherein:
[0038] FIG. 1 is a schematic image of an authenticatable article,
specifically a coin, bearing an overt security feature;
[0039] FIG. 2 is a schematic illustration of a system for producing
an authenticatable article;
[0040] FIG. 3 is a flow chart illustrating a method for producing
an authenticatable article;
[0041] FIG. 4 is a schematic illustration of a system for
authenticating an authenticatable article; and
[0042] FIG. 5 is a flow chart illustrating a method for
authenticating an authenticatable article.
DETAILED DESCRIPTION
[0043] The methods and systems described herein are useful for
authenticating valuable articles which may include any physical
object capable of reproducible fabrication including the production
of a particular feature by predetermined means which is
characterized both by determinable physical properties and random
or probabilistic physical properties. In particular, the article
may be a coin or banknote, an investment commodity such as a
bullion coin or bar, or may be a luxury item such as an article of
designer apparel or accessory. Coins may include coins, wafers,
bars, bullion, medallions, medals, security tokens, ornaments,
circulation coins, numismatic coins, investment coins. Coins may be
made of base metals, precious metals, or both. The exemplary
embodiments described below are based on the selection of the
article as being a coin, which may be currency or bullion, but it
will be understood that such selection is required by convenience
of exposition only and does not limit the scope or intent of the
solution.
[0044] The physical properties of the applied feature may include
any properties which are measurable. Embodiments below assume that
the determinable properties include macroscopic size, shape, and
configuration of the feature, while the random or probabilistic
physical properties include a surface topology of the feature.
Again, such selections are required by convenience and do not limit
the solution. In any event, the randomness or probabilistic nature
of the feature results not from a selective control of the
fabrication technology with this purpose, but rather results from
the nature of the fabrication technology itself which
uncontrollably produces the random or probabilistic topology.
[0045] This overt feature may be produced using any convenient
fabricating technique according to the article material
involved.
[0046] There are many known methods for producing features on
coins, for example, wherein the characteristics of the feature are
generally controllable. Thus, the physical transformation involved
and the resulting feature can be orderly rather than random or
probabilistic, and may include, for example, an engraved design, a
print made by known methods (pad printing, gravure printing, inkjet
printing, lithography printing, silk printing, intaglio printing),
an affixed or stamped hologram, 2D matrix code, bar code, QR code,
and so forth. Such methods and the resulting features, however, may
remain precisely reproducible by counterfeiters, and thus provide a
lesser degree of security than methods and features which in their
nature involve some random or probabilistic aspect such that the
resulting feature is not precisely reproducible. A counterfeiter in
such circumstances need not deduce the method of authentication
ultimately employed as it would be possible to make an exact
duplicate of the authentic article. Consequently, any signature or
authentication code generated therefrom would be identical whether
the article were authentic or a forgery. While the techniques
described herein may include production of a feature by such
methods, enhanced security may be achieved by employing a method
involving a random or probabilistic aspect.
[0047] Thus, where the article is a coin, useful fabricating
techniques including an uncontrolled random or probabilistic aspect
suitable to produce a non-reproducible feature may include laser
engraving, acid etching, photosensitive etching, random dot machine
engraving, sandblasting, and so forth. Such techniques are useful
to transform a natural topography of the article material into an
irreversible and permanent physical feature which is impossible
precisely to replicate and has a visibly changed appearance of the
material, while at the macroscopic level rendering a reproducible
physical form. The fabricating technique may be selected based on
the article material so as to produce the random or probabilistic
aspect or characteristic having a predetermined coarseness such
that it is capable of reliable digital imaging using simple,
commonly-available imaging technology. As noted above, in one
embodiment the desired degree of coarseness or surface roughness
may be expressed as that which makes possible reliable digital
imaging at a magnification of about 20 times.
[0048] Reference is made to FIG. 1 which shows an exemplary
authenticatable article, namely a coin 50. The coin 50 may have
reproducible design elements 60 as are typically provided along
with identifying marks 70 which may be a denomination or any other
such matter useful to identify a relevant characteristic of the
coin or its use. In the example, the identifying mark 70 is shown
as a weight which is typically provided in the case where the
exemplary coin is bullion. The design elements 60 and identifying
mark 70 are typically produced identically on each member of a
number of articles produced using the same means, such as a tool,
die, mold, or so forth. The coin 50 also has an overt security
feature 80 produced as described herein. The feature 80 may be a
design element and detectable by normal human vision without visual
aids. For example, the feature may be a well-recognized icon such
as a maple leaf, and may be immediately recognized as such by a
person observing the coin. By virtue of the manner of its
fabrication, however, the feature is characterized by properties
which are random or probabilistic and thus the feature is not
precisely reproducible.
[0049] For example, where the article is a coin and the feature is
produced using the fabrication technology of laser engraving, the
feature will appear frosted to the naked eye which at the
microscopic scale results from a random or probabilistic
distribution of raised points and various shapes of different
sizes, reflectivities, and surface roughness. In general, the
frosting effect cannot be exactly replicated with the exact details
and this gives the feature its uniqueness. Different fabrication
technologies may produce different physical transformations which
may be measured or imaged and used to generate a signature. For
example, sandblasting creates on a metal surface a random
distribution of grain structure. Other technologies may be used
which similarly produce random or probabilistic, or generally
uncontrollable, physical transformations or patterns which may be
used to generate a signature.
[0050] Reference is made to FIG. 2 which shows a system 100 for
producing the high security article capable of reliable
authentication as described herein. The system 100 may include an
article fabrication means 110, a feature application means 120, and
a feature reading means 130. The article fabrication means 110 is
useful to produce the article in all its aspects absent the overt
security feature. The feature application means 120 is useful to
produce on the article so manufactured the feature including the
determinable properties such as size and shape, as well as the
random or probabilistic properties such as the surface topography.
The feature reading means 130 is useful to read or measure the
random or probabilistic properties of the overt feature. In some
embodiments, the system 100 may omit the article fabrication means
110 when the article is provided already fabricated and ready to
have the feature applied thereon by the feature application means
120.
[0051] The feature application means 120 may include any components
or aspects as are necessary or desirable according to the
technology employed to produce the feature in the article, and may
encompass known aspects of any of the fabrication technologies
described herein or functional alternatives. For example, and
without limiting the generality of the solution desired herein, the
overt security feature may be a maple leaf produced by laser
engraving and have micro-engraved therein another symbol such as
the numeral "13". The maple leaf may be conspicuous and easily
recognizable by the unaided eye, while the numeral "13" may require
a loupe to recognize. The maple leaf may have a roughened texture
resulting from its means of fabrication.
[0052] Similarly, the feature reading means 130 may include any
components or aspects as are necessary or desirable according to
the technology employed to produce the feature in order to read,
measure, image, or otherwise determine the random or probabilistic
properties of the feature so created, and for example may include
any sensors suitable to measure or determine the properties. The
feature reading means 130 may include or cooperate with other
aspects to facilitate measurement or imaging of the feature, and
may include in some embodiments a holder which may incorporate a
source of controlled illumination, a special lens and a locator
which permits the coin or other article to be positioned in a
predetermined position, within predetermined tolerances. The
feature reading means 130 may further include or cooperate with
imaging sensors, such as a camera, which may constitute an imaging
system 135.
[0053] The system 100 may include processing means 140 connected to
or otherwise cooperating with the feature reading means 130 or
imaging system 135 to generate and obtain the measurement or image
of the feature. The processing means 140 may be further configured
to encode the measured feature and to combine it with other
information for any desired purpose including, for example, to
generate a digital signature. The processing means 140 may include
or be configured with software containing algorithms for digitally
coding the measurement or image of the feature, and may also be
configured to generate virtual identification numbers referencing
to the design of the article or tooling or die used to make it, as
the case may be, for generating the authentication signature.
[0054] In one aspect, the feature may be considered to result in or
embody two types of codes, code type p and code type v, which are
generated by the processing means 140.
[0055] Type p may be a physical code based on the physical
structure of the transformed material in the design, and the design
itself, which is specific to each coin or other article, if the
transformation is made in coin or article, or to the die, mold,
punch, or matrix, as the case may be. In the latter case, a family
of coins or other articles will have the same code since they come
from the same die, etc.
[0056] Type v may be a virtual code generated from virtual
references linked to the physical designs just created by the
transformation and physical reference points of the original design
being part of the untransformed material on the coin or other
object, if the transformation is made in the object or the coin, or
to the die, etc., if the material transformation is made in the
original die, etc. In this latter case, a family of coins or other
articles will have the same code since they come from the same die,
etc. Such references may include, for example, physical features of
a design, a form, visible reference points, or locations or details
visible only under magnification, or the relative positioning of
key features hidden in the created design and which are only known
to the manufacturer of the object or the coin.
[0057] Both codes, types p and v, may then be combined by the
processing means or otherwise used in accordance with a predefined
algorithm to produce a digital signature associated with the coin
or other article, or die, etc. used to produce it, as the case may
be.
[0058] Thus, in the example of the maple leaf feature produced as
described above, the digital signature may be derived using
algorithms encoded in the processing means based on the measured
random or probabilistic topographical properties of the feature
combined with a detail of the original design of the coin, for
example the engraved letters "OZ" in the weight indication 70 shown
in FIG. 1. The authentication signature derived from such
combination thus incorporates both a type p code, e.g. vectors
related to the physical nature of the material transformation, and
a type v code which is a virtual code which uses virtual references
of the created design and the original design, e.g. identification
of the maple leaf and the "OZ" weight indication.
[0059] The system 100 may further include a database 150 connected
to the processing means 140 for storing the authentication
signature.
[0060] A method 200 for producing an article which may be
authenticated as described herein will now be described with
reference to FIG. 3. In the method, the overt feature is made,
fabricated, produced, or otherwise provided in the article (step
210). The feature is associated with the product and may identify
visually the security feature of the article. For example, where
the article is a coin, the feature may be produced by laser
engraving the coin surface in a predetermined location with a
predefined design. Laser engraving transforms the surface of the
coin from a smooth finish to a rough, lumpy finish at the
macroscopic scale. This lumpy finish appears as a frosty finish
design to the human eye, but under proper magnification the
laser-transformed surface has a structure of 3D randomly
distributed material which is physically and permanently changed.
An observer of the coin seeing the feature may then be aware of the
presence of the security feature.
[0061] An image of the coin is then collected including in the area
containing the overt feature produced in the previous step (step
220). The image may be collected under preselected lighting
conditions using any suitable sensors and equipment, e.g. with a
camera. The camera is connected or otherwise configured to
communicate the image to a server encompassing the processing
means. The camera may be provided with any such lenses or other
equipment as are necessary or desirable for collecting a suitable
image of the overt feature. For example, if a lens of the camera
does not provide enough magnification detail, it may be
supplemented or replaced with a special lens and special diffused
lighting to obtain clarity and illumination without intense glaring
and light reflection.
[0062] The processing means, having received the collected image
from the camera, may be provided with software or otherwise
configured to process the image as desired (step 230). For example,
the processing means may be configured to decompose the image into
vector elements, to classify elements therein, to analyze the
elements according to predefined algorithms, and to encode the
similarities and the differences to produce a digital code which
characterizes the article. Articles having precisely identical
physical features would result in the same digital code. Moreover,
the digital code may capture all of the common features of the
transformed image on the article which may include the 2D/3D
surface finish, the form, and the relative physical structure of
the material matter.
[0063] As discussed above, the code so generated may have two
components: the component type p based on the random or
probabilistic physical properties of the feature, and the component
type v based on a virtual reference which is generated by the
software. This virtual reference may be linked to the physical
reference. In general, the code may combine information based on
the random or probabilistic physical properties of the feature as
well as information or identifiers common to the category of coins
(e.g. the presence of the letters "OZ") as well as information
regarding the category of the security feature (e.g. that it is a
maple leaf).
[0064] Once the digital authentication code is generated, it may be
communicated to and stored in a database (step 240). As indicated
above, if the feature is applied to each individual coin or other
article, then the authentication code generated therefrom will be
unique to that particular coin or article, whereas if the feature
is applied to means for producing the article, such as a die or
mold used to make a coin, then the feature will be applied to each
coin made using that die or mold and thus the authentication code
will uniquely identify all of the coins made using that die or mold
without distinguishing between them.
[0065] Where a number of articles or families of articles are thus
produced each having a unique overt security feature and a
correspondingly unique authentication signature, the database may
contain all such authentication signatures for later use to
authenticate any one of the articles or families.
[0066] Reference is made to FIG. 4 which shows a system 300 for
authenticating a high security article as described above. The
system 300 includes a feature reading means 330 useful to read or
measure the random or probabilistic properties of the overt
feature. The feature reading means 330 of the authentication system
300 may be of the same type or a different type from the feature
reading means 130 of the article production system 100. The feature
reading means 330 may include any components or aspects as are
necessary or desirable according to technology employed to produce
the feature in order to read, measure, image, or otherwise
determine the random or probabilistic properties of the feature,
and for example may include any sensors suitable to measure or
determine the properties. As in the example developed above, the
feature reading means 330 may include or cooperate with a holder
which may incorporate a source of controlled illumination, a
special lens and a locator which permits the coin or other article
to be positioned in a predetermined position, within predetermined
tolerances. The feature reading means 330 may include or cooperate
with such suitable imaging sensors, such as a camera, which may
constitute an imaging system 335.
[0067] The system 300 may include processing means 340 connected to
or otherwise cooperating with the feature reading means 330 or
imaging system 335 to generate and obtain the measurement or image
of the feature. The processing means 340 may be further configured
to encode the measured feature and to combine it with other
information for any desired purpose including, for example, to
generate a comparison signature. The processing means 340 may
include or be configured with software containing algorithms for
digitally coding the measurement or image of the feature, and may
also be configured to generate virtual identification numbers
referencing the design of the article or tooling or die used to
make it, as the case may be, for generating the comparison
signature. Finally, processing means 340 may also include or be
configured with software algorithms for comparing the comparison
signature with the database of previously-generated authentication
signatures to determine a match, or otherwise to determine whether
the comparison signature indicates that the associated article is
authentic within predefined tolerances.
[0068] The system 300 may further include a database 350 connected
to the processing means 340 for storing the comparison signature.
The database 350 may be one and the same as the database 150
containing the authentication signatures as discussed above, or it
may be a separate database. Alternatively, the comparison signature
may not be stored in a database, but may rather be stored in a
transient memory for the purpose of comparing the comparison
signature to the authentication signatures stored in database 150,
wherein again database 350 is one and the same as database 150. The
system 300 may further include a display 360 for displaying a
result of a comparison of the comparison signature and any
authentication signature, or for displaying results of the
authentication process more generally.
[0069] In one embodiment, the authentication system 300 includes a
portable device equipped with a camera such as a smartphone which
may include an accessory comprising an optical system such as is
described in U.S. Pat. No. 7,995,140B2 which is included herein by
reference. In such case, the feature reading means 330 includes the
smartphone or an aspect thereof, and the imaging system 335 may
include the camera and imaging features generally of the
smartphone. The smartphone may be preconfigured with software
operative to perform the functions described herein, including to
select from an image of an article collected using the smartphone
camera an area of interest on the article to be authenticated, and
to send the image to a preconfigured network location such as an
Internet website. Alternatively, the smartphone may be configured
to send an entire image captured to the network location. Further
alternatively, the smartphone may be used to navigate to such
location by means and methods known in the art and the image
uploaded manually. The processing means 340 in some instances may
include an aspect of the processing means of the smartphone. In
general, the processing means 340 may include processing means of
the remote data processing server to which the image was sent by
the smartphone.
[0070] Upon receipt of the image at the server, the image may be
decomposed, analyzed, coded with preconfigured software algorithms,
and a comparison signature may be generated. By comparing the
comparison signature generated from the article to be authenticated
against the pre-generated and stored signatures in the database a
match or lack of match of the coded signatures may be determined
within predefined tolerances. Thus, the previously-generated
authentication signatures were generated from the same
predetermined acquisition area on the article, using the same
method of decomposition of the image, the same software algorithms,
and the same procedural approach for encoding. The result of the
match comparison may be communicated back to the smartphone and
displayed on a screen of the smartphone, in which case such screen
may constitute an aspect of the display 360 of the system 300. The
result may thus be displayed to a user of the smartphone thereby
informing them as to whether a positive match has been found, and
thus the article at issue is identified as authentic, or whether a
match could not be found, and thus the article is identified as
inauthentic or suspect, within the time to carry out the
communications and processing described above.
[0071] Alternatively, the authentication system 300 may include a
generally non-portable device such as authentication equipment at
point-of-sale or in a bank branch or other facility. In such case,
the feature reading means 330 may include an imaging system 335
including a camera, lenses, lighting, and so forth, and may further
include a preconfigured holder, sorter, or any other additional
aspects to facilitate the authentication process. In some cases,
the processing means 340 may be collocated with the feature reading
means 330, and the databases 150, 350 may either be remote or also
collocated with the feature reading means 330. This would be
particularly likely where the authentication system 300 is located
in the premises where the article was produced. The display 360 in
such case may include a monitor connected with the processing means
340 to display the result of the authentication process. As
compared to the embodiment described above wherein the feature
reading means 330 includes a smartphone, a non-portable device
located at point-of-sale or in a bank branch or other such facility
may be provided with an imaging system and cooperating lenses,
lighting, etc. so as to obtain a better image of an overt security
feature and may thus be rendered more reliable in determining the
authenticity of the article.
[0072] In further embodiments the feature reading means 330 and
imaging system 335 may include a computer and a webcam operatively
attached to the computer for capturing an image of the article to
be authenticated, wherein the image is communicated via a network
to a server for generating the comparison signature and testing it
against a database of authentication signatures, as described
above, and the display includes a monitor operatively connected to
the computer for displaying a result communicated in return from
the server.
[0073] A method 400 for authenticating an article as described
herein will now be described with reference to FIG. 5. In the
method, an image of the overt feature is collected, or it is
otherwise read or measured (step 420). The image may be collected
under preselected lighting conditions using any suitable sensors
and equipment, e.g. with a camera. The camera may be connected or
otherwise configured to communicate the image to a server
encompassing the processing means. The camera may be provided with
any such lenses or other equipment as are necessary or desirable
for collecting a suitable image of the overt feature. For example,
if a lens of the camera does not provide enough magnification
detail, it may be supplemented or replaced with a special lens and
special diffused lighting to obtain clarity and illumination
without intense glaring and light reflection.
[0074] The processing means, having received the collected image
from the camera, may be provided with software or otherwise
configured to process the image as desired (step 430). For example,
the processing means may be configured to decompose the image into
vector elements, to classify elements therein, to analyze the
elements according to predefined algorithms, and to encode the
similarities and the differences to produce a digital comparison
code which characterizes the article.
[0075] As in the case with the original authentication codes
discussed above, the comparison code so generated may have two
components: the component type p based on the random or
probabilistic physical properties of the feature, and the component
type v based on a virtual reference which is generated by the
software. This virtual reference may be linked to the physical
reference, and the comparison code may combine information based on
the random or probabilistic physical properties of the feature as
well as information or identifiers common to the category of coins
(e.g. the presence of the letters "OZ") as well as information
regarding the category of the security feature (e.g. that it is a
maple leaf).
[0076] Once the digital comparison code is generated, it may be
compared or otherwise tested against the authentication codes
already generated and stored in the database (step 440). A
determination is then made whether the comparison code matches or
otherwise tests positively against any of the authentication codes
within predefined tolerances (step 450). The results of this
comparison may then be communicated for display to a user (step
460). The result so displayed may include simply an indication that
the article is authentic, or alternatively inauthentic or suspect,
within the predefined tolerances. Alternatively, the displayed
result may include further information including, for example, an
indication of the origin of the article where the comparison and
authentication signatures commonly correspond to a particular
origin, or where the feature has been applied to the means for
fabricating the article such as a die for a coin, the display may
further indicate the lot number or other identification of the
family of articles to which the tested article belongs.
[0077] By employing the systems and methods described above, a
feature may be produced on a valuable article wherein the feature
is visible and recognizable to the unaided eye and may be further
recognized as embodying a security feature, but is produced using a
fabrication technology which includes a random or probabilistic
aspect such that the feature once produced cannot be precisely
reproduced.
[0078] As noted above, where the feature is applied to means for
producing the valuable articles--on the die used to strike coins,
for example--then all of the articles made using those means will
bear identical replicates of the feature. The signature derived
therefrom may then serve to identify and authentication the family
of articles, such as all of the coins struck using a die bearing
the feature, for example. The fact that the feature bears a
determinable and reproducible aspect observable by the unaided eye,
but which also contains random or probabilistic features, enables
the production of lots or groups of articles which appear to be
identical to the unaided eye, but which may be distinguished based
on such random or probabilistic features.
[0079] For example, a number of dies may be produced each bearing
an identical coin design and having an instance of an overt feature
having the same identical shape and configuration, applied in each
case using the same fabrication technology. The feature on each die
will be differentiated, however, by the random or probabilistic
properties produced thereon as a result of the fabrication
technology. The result will be that all coins struck from all of
the dies so produced will appear to the unaided eye to be
identical, but each coin may be analyzed to determine from which of
the number of dies it was struck as the coins struck by each die
will bear the random or probabilistic properties present on that
particular die which are different from the properties present on
any of the other dies and hence the coins produced using such
dies.
[0080] In one embodiment, where the feature is applied to the means
of making the article--on the die used to strike coins, for
example--it may happen that repeated production of articles using
the means in significant numbers may result in a degradation or
other change of the relevant random or probabilistic properties of
the feature. For example, a feature on a die used to strike coins
may be degraded over time by mechanical stress. Any coins
subsequently struck from the same die would bear the changed
feature. Depending on the particulars of the algorithm used to
generate the signature, such change may result in a change to the
signature so generated. The issue might therefore arise whether an
authentication signature originally generated in connection with
the feature when first applied and functional to authenticate coins
produced at an early stage would continue to identify as
authenticate coins produced at a later stage bearing the degraded
or changed feature. Left unaddressed, the degradation in the
feature on the die might progress to such an extent that coins
produced by the die at a later stage would not be identified as
authentic with reference to the authentication signature originally
generated.
[0081] In order to account for an expected degradation or other
change in the feature on the die or other means of production, a
number of strategies are possible. For example, a single
authentication signature useful for authenticating all coins
produced by the die over its lifespan may be recalculated from
time-to-time based on an average, such as a moving average, of the
original authentication signature as well as further authentication
signatures calculated from the degraded feature at predefined
intervals. Factors which may be taken into account in making the
recalculation may include the type of fabrication process involved,
the selection and nature of both the overt and covert features of
the article, and differences between the system used to generate
the authentication signature and the systems to be used to
authenticate the articles afterward. Any appropriate number of
times or intervals may be selected, and may include a few times
during the useful life of a die, for example. Alternatively, a
further authentication signature may be determined from
time-to-time and added to the database as an additional
authentication signature associated with that die. Thus, a single
die may have associated with it a number of authentication
signatures based on the feature in a number of states or extents of
degradation, and thus a single die may have a number of valid
signatures. While the features reproduced on coins will be
identical to the unaided eye regardless of their extent of
degradation in this connection, they may be differentiated based on
their extent of degradation by means of the different corresponding
authentication signatures derived therefrom. Thus, the
authentication signature may be used not only to determine which
die was used to produce any particular coin, but at what point in
the lifecycle of the die the coin was struck.
[0082] The above systems and methods may be particularly useful
where the article is a coin made of a dense material such as gold
or platinum wherein the material tends to have dense surface
morphology and unclear grain boundaries under normal magnification
of 20 times. The present methods are operative even at low
magnification and thus low cost equipment is sufficient to capture
a suitable image.
[0083] In the preceding description, for purposes of explanation,
numerous details are set forth in order to provide a thorough
understanding of the embodiments of the invention. However, it will
be apparent to one skilled in the art that these specific details
are not required in order to practice the invention. In other
instances, well-known electrical structures and circuits are shown
in block diagram form in order not to obscure the invention. For
example, specific details are not provided as to whether the
embodiments of the invention described herein are implemented as a
software routine, hardware circuit, firmware, or a combination
thereof.
[0084] Embodiments of the invention can be represented as a
software product stored in a machine-readable medium (also referred
to as a computer-readable medium, a processor-readable medium, or a
computer usable medium having a computer-readable program code
embodied therein). The machine-readable medium can be any suitable
tangible medium, including magnetic, optical, or electrical storage
medium including a diskette, compact disk read only memory
(CD-ROM), memory device (volatile or non-volatile), or similar
storage mechanism. The machine-readable medium can contain various
sets of instructions, code sequences, configuration information, or
other data, which, when executed, cause a processor to perform
steps in a method according to an embodiment of the invention.
Those of ordinary skill in the art will appreciate that other
instructions and operations necessary to implement the described
invention can also be stored on the machine-readable medium.
Software running from the machine-readable medium can interface
with circuitry to perform the described tasks.
[0085] The above-described embodiments of the invention are
intended to be examples only. Alterations, modifications and
variations can be effected to the particular embodiments by those
of skill in the art without departing from the scope of the
invention, which is defined solely by the claims appended
hereto.
* * * * *